View Full Version : sheet aluminum for siding-what alloy

04-09-2006, 03:24 AM
My 'apprentice' brought over some aluminum which is used on the sides of some semi trailers. It looks like plain old al sheet, but it doesn't like to be bent. It will crack badly on the outside of the bend, and if you bend it back it wants to break off right away. This stuff is already painted on one side, but seems like ordinary sheet to me, until you bend it. It shears fine.

Just wondering if I can put a label on this stuff, since it seems I've acquired some, and I don't want to be collecting a stash of mysery metal.

04-09-2006, 08:59 AM
Used to make the stuff. But that was a long time ago so... My first guess would be a 5xxx series (5052,5182) that has been strain hardened.

You can easily anneal it in smaller pieces with a propane torch.

04-09-2006, 09:22 AM
A quick lookup finds this:

Aluminum Siding, Soffit and Fascia
• Siding, soffit and fascia are made of 3105 or equivalent aluminum alloy.
• Soffit is H18 or equivalent hardness, siding and fascia H16 or equivalent. Thickness: 0.019 nominal 0.024 nominal
• Meets performance requirements of AAMA 1402-86.


04-09-2006, 10:22 AM
I agree with topco it is a 5xxx alloy used on semi trailers. House siding is usually a 3xxx series alloy. In a lot of cases guttering was made from reject can stock and we called it H19. Also use to make the stuff.


04-09-2006, 01:32 PM
Hm, interesting. Thanks guys. There's some info I can pass along. Judy will be able to blow them away at her work with this knowledge.